Parts of Sunset Harbour Stormwater System Not Performing as Expected:

Lanzo construction to submit plans for improvements

Parts of the new stormwater system in Sunset Harbour are not working to their intended capacity. City Manager Jimmy Morales notified Commissioners that during a heavy rain event on Sunday “some localized flooding was observed at various locations throughout the City” but the rain should not have been enough to cause flooding in Sunset Harbour.

Morales wrote in a Letter to Commission that in the 24-hour period ending at midnight Sunday, 4.09 inches of rain fell at City Hall. Between the hours of 6 and 7 pm Sunday evening, 1.88 inches of rain fell with a peak intensity of 8.11 inches per hour.

“In Sunset Harbour on Sunday evening, some properties that are located below the flood plain elevation reported minor flooding for a brief period of time,” Morales wrote.

Built by Lanzo Construction Company, the new system “was expected to prevent sunny day flooding due to sea level rise and manage six (6) inches of rain in 24 hours with a peak hourly capacity of 2.4 inches,” according to Morales. “The improvements have proven to work very well against sea level rise as we have not seen any sunny day flooding in the area which had been frequently the case during higher tidal events.”

But, as Morales explained, the system is not performing to that expected capacity during rain events. “[T]he system, in at least some locations, reaches capacity at 1.8 inches in one hour.”

Local businesses and Commissioner Kristen Rosen Gonzalez have expressed frustration at the flooding that still occurs in some areas of Sunset Harbour during rain storms. According to Morales, “City staff, consultant engineers from AECOM, and Lanzo Construction Company with their engineers from Wade Trim, have been engaged for months making this determination.”

“Lanzo Construction Company owner, Joe D’Alessandro Sr., has provided his commitment to the City of Miami Beach to make improvements in the system to be sure expectations are met,” Morales said. The company is expected to submit plans for system improvements soon and, “Work is expected to commence very shortly."

In the meantime, “If the City experiences rainfall events that exceed 1.8 inches per hour, exceeding the system capacity, properties that are below the flood plain elevation may experience standing water for a short amount of time,” Morales said.

Sunset Harbour was the first project in the City's $400 million resiliency program. It included a new stormwater system, pumps, and elevated roads.